Today, batteries in implanted medical devices have a limited lifespan, some needing replacement within seven to 10 years depending on use. Increasing clinical applications, for example wireless monitoring of cardiac pacemakers, and the continuous drive to design less obtrusive implanted devices, is placing further strains on battery operating lifetimes.
While some implanted device batteries can be externally recharged, more commonly the patient must undergo a time-consuming and costly surgical replacement of the entire device. It is estimated that surgical replacement of a cardiac pacemaker can cost up to GBP10,000.
The two-year SIMM (self-energizing implantable medical micro system) project will prototype a device capable of harvesting energy from movement in or on the body, including joint movement and heartbeats. Body energy will be harvested by means of a microgenerator manufactured as a micro-electrical-mechanical system, or MEMS. This prototype design is expected to achieve 10 to 100 times more power than previous attempts to harvest human energy.
According to industry research, there is great demand for improved power supply technology in many emerging medical applications, including neurostimulation, activity monitoring, bladder control valves, drug delivery systems, medical telemetry and cochlear and retinal implants.
The project has received GBP500,000 in funding from the UK Department of Trade and Industry (DTI), which will be match-funded by the consortium.
Other companies involved in the SIMM project consortium are Finsbury Orthopaedics, Innos, InVivo Technology, Odstock Medical, and Perpetuum Ltd.
A proof of concept prototype as a result of the project is expected to be released in 2007.